Technical Abstract:
The Nutrient Data Laboratory (NDL), Beltsville Human Nutrition Research Center, USDA is working with the Office of Dietary Supplements (ODS), NIH, to plan and develop a Dietary Supplement Ingredient Database (DSID) to monitor the levels of ingredients in dietary supplement products. For dietary supplements, priority product categories were identified based on prevalence data. The most common dietary supplements reported were multivitamin/mineral products. Ingredients in dietary supplements were ranked based on exposure (NHANES data), public health significance, research significance, and the availability of reference materials and validated analytical methods of analysis. Using this scheme, seven high priority (Tier 1) nutrients were identified for initial pilot study work: folic acid, vitamin C, vitamin A (retinol and beta-carotene), vitamin E (alpha-tocopherol), calcium, and iron.
In this pilot study, methods of analysis and sample handling procedures and protocols for addressing nutrient stability and encapsulation, sample homogenization and storage conditions were compared and evaluated. Tier 2 nutrients were then identified; these include an additional seven vitamins and nine minerals. Multivitamin/minerals were analyzed for these nutrients by qualified laboratories and their methods and protocols compared and evaluated. Representative multivitamin/mineral supplement products were then identified from NHANES data using statistical sampling techniques. These will be tested for any systematic relationship between label values and actual values and to assess the nutrient variability between products labeled at the same level. The results of these pilot studies will be used to plan a nationwide sampling of multivitamin products.
The major product of this research will be a publicly available database containing a mix of data types and product types. This will enable dietitians and other nutrition professionals to assess the total nutrient intake from foods, beverages, and dietary supplements. The DSID will be maintained and made available to the public on NDL’s website: www.nal.usda.gov/fnic/foodcomp.